Fish gelatin/chitosan blend films incorporated with betel (Piper betle L.) leaf ethanolic extracts: Characteristics, antioxidant and antimicrobial properties

Mechanical, barrier, and thermal properties of biodegradable films prepared using different gelatin/chitosan blends without and with betel leaf ethanolic extract (BLEE) at 1 and 2% were investigated. Incorporation of BLEE enhanced elasticity and heat-seal ability of the films. However, the seal ability was diminished with increasing chitosan proportion (p < 0.05). Ultraviolet and visible light barrier abilities along with water vapor permeability were improved (p < 0.05) for films containing 2% BLEE. Swelling and water solubility of the films were lessened with augmenting BLEE concentrations (p < 0.05). Antioxidant and antibacterial activities were upsurged as BLEE levels incorporated increased. SEM images of selected films showed smooth homogenous surface and cross-section in film sample devoid of BLEE, while those incorporated with BLEE had slightly rough surface and cross-section. FT-IR spectra revealed differences in peaks and patterns between films without and with BLEE. Addition of BLEE enhanced thermal stability of film. Thus, gelatin/chitosan films containing BLEE could serve as active packaging with satisfactory properties.